Benzene is a volatile organic compound (VOC) that is an important solvent and used in the production of drugs, plastics, synthetic rubber and dyes.

Ambient air may contain low levels of benzene from automobile service stations, wood and tobacco smoke, and exhaust from motor vehicles and industrial emissions. About 50% of the exposure to benzene in the United States results from smoking tobacco or from exposure to tobacco smoke.

Benzene exposure has serious health effects and is classified as a human carcinogen. Long-term exposure to excessive levels of benzene in the air causes leukemia, a potentially fatal cancer of the blood-forming organs.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". It is possible that more than one standard could seem to apply in evaluating the potential health risk of a particular situation; however, the standard that is officially applied is the one set by the regulating agency (or agencies) charged with protecting human health in the context of that particular environment.

The standards for regulation of exposure to Benzene are from the California Office of Environmental Health Hazard Assessment.

Carbon Disulfide

Carbon Disulfide is a volatile organic compound (VOC) that is often found in industrial processes.

In its pure form it has a smell similar to chloroform but when contaminated, it produces a smell that is similar to rotting radishes.

In nature, small amounts of carbon disulfide are found in gases released to the earth's surface including volcanic eruptions or over marshes.

Short term exposure to carbon disulfide can result in irritation to the eyes, skin, and mucous membranes. Long term exposure can result in damage to the nervous system and coronary heart disease.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Carbon Disulfide are from the California Office of Environmental Health Hazard Assessment.

Hydrogen Sulfide

Hydrogen sulfide occurs naturally in petroleum, natural gas, volcanic gases, and hot springs. It is also found in many waste streams and is easily identified by its distinctive "rotten egg" odor.

Short term exposure to hydrogen sulfide can result in irritation to the eyes and mucous membranes.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Hydrogen Sulfide are from the California Office of Environmental Health Hazard Assessment.

Ozone

Ozone is a colorless, odorless reactive gas comprised of three oxygen atoms. It occurs naturally in the earth's stratosphere, where it is beneficial as it absorbs the ultraviolet component of incoming solar radiation that could be harmful to life on earth. However, ozone is also found near the earth's surface where pollutants such as nitrogen oxides (NOx) and volatile organic compounds (VOCs) combine with carbon monoxide (CO).

Ozone can be an irritant to the lungs, inflaming lung tissue and aggravating respiratory illnesses such as bronchitis and asthma.

Currently there are no standards set for evaluating risks of exposure to Ozone.

Sulfur Dioxide

Sulfur dioxide is a product of combustion from coal and other fuel burning. There are natural sources of atmospheric SO2, including volcanoes. Sulfur dioxide is used as a food preservative for some fruits and vegetables; as a disinfectant; for bleaching flour, fruit, grain, wood pulp, wool, textile fibers, gelatin, and glue; and for making other chemicals.

Common sources of sulfur dioxide in ambient air include refineries, power plants, trains, ships, trucks and automobiles. Possible health effects: Sulfur Dioxide (SO2) can be an irritant to the lungs, inflaming lung tissue and aggravating respiratory illnesses such as bronchitis and asthma.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". It is possible that more than one standard could seem to apply in evaluating the potential health risk of a particular situation. Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Sulfur Dioxide are from the California Office of Environmental Health Hazard Assessment. No chronic exposure standard is set by OEHHA.

Toluene

Toluene occurs naturally as a component of petroleum and is produced in petroleum refining and coke oven operations. Toluene is commonly found in household aerosols, nail polish, paints and paint thinners, lacquers, rust inhibitor, adhesives and solvent based cleaning agents.

Toluene can be an irritant to the nose, throat and eyes, respiratory tract, and can cause headaches.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Toluene are from the California Office of Environmental Health Hazard Assessment.

Xylene

Xylenes are a clear, colorless, sweet-smelling liquid. Xylenes are found naturally in petroleum, coal tar, and wildfires. Xylenes are commonly used in industrial solvents, paints, varnishes, dyes, adhesives, detergents, and pharmaceuticals.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Xylenes are from the California Office of Environmental Health Hazard Assessment.

Community Monitoring Chemical Definitions

Chemical

Description

Ambient Air Quality Standards

2,2,4-Trimethylpentane

2,2,4-Trimethylpentane is produced in the petroleum industry by distillation of petroleum. It is an important component of gasoline, frequently used to prevent automobile engines from knocking during the combustion of the fuel.

2,2,4-Trimethylpentane causes eye irritation and irritation of the respiratory tract.

Currently there are no standards set for evaluating risks of exposure to 2,2,4-Trimethylpentane

3-Methylpentane

3-Methylpentane is produced during the separation processes of hydrocarbons. Natural sources of 3-methylpentane include petroleum, natural gas and ocean water.

The gas is harmful if inhaled and can cause irritation of the respiratory tract with burning pain in the nose and throat, coughing, wheezing, and shortness of breath.

Currently there are no standards set for evaluating risks of exposure to 3-Methylpentane.

Ammonia

Ammonia is a colorless gas that has a very distinct pungent odor. Ammonia is found in certain household cleaners, and is the building block of many commonly used items such as fertilizer.

It is primarily an eye and upper respiratory tract irritant. Individuals who have asthma or other respiratory tract problems should avoid long-term exposure to ammonia.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of Ammonia cited below are from the California Office of Environmental Health Hazard Assessment.

Benzene

Benzene is a volatile organic compound (VOC) that is an important solvent and is used in the production of drugs, plastics, synthetic rubber and dyes.

Ambient air may contain low levels of benzene from automobile service stations, wood and tobacco smoke, and exhaust from motor vehicles and industrial emissions. About 50% of the exposure to benzene in the United States results from smoking tobacco or from exposure to tobacco smoke.

Benzene exposure has serious health effects and is classified as a human carcinogen. Long-term exposure to excessive levels of benzene in the air causes leukemia, a potentially fatal cancer of the blood-forming organs.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". It is possible that more than one standard could seem to apply in evaluating the potential health risk of a particular situation; however, the standard that is officially applied is the one set by the regulating agency (or agencies) charged with protecting human health in the context of that particular environment.

The standards for regulation of exposure to Benzene are from the California Office of Environmental Health Hazard Assessment.

Black Carbon

Black carbon, or soot, is a type of dark particulate matter produced by the incomplete combustion of fossil fuels, wood, and other biofuels. It commonly originates from motor vehicles, residential stoves/fireplaces and forest fires.

Black Carbon can be an irritant to lung health, inflaming the lungs and aggravating respiratory illnesses such as bronchitis and asthma.

Currently there are no standards set for evaluating risks of exposure to Black Carbon.

Ethylbenzene

Ethylbenzene is commonly found in refineries as a component of petroleum and is also an ingredient in some paints and solvents.

The acute toxicity of Ethylbenzene is low and there is limited information on long-term health impacts.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". It is possible that more than one standard could seem to apply in evaluating the potential health risk of a particular situation. Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Ethylbenzene are from the California Office of Environmental Health Hazard Assessment. No acute exposure standard is set by OEHHA.

Hydrogen Sulfide

Hydrogen sulfide occurs naturally in petroleum, natural gas, volcanic gases, and hot springs. It is also found in many waste streams and is easily identified by its distinctive "rotten egg" odor.

Short term exposure to hydrogen sulfide can result in irritation to the eyes and mucous membranes.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to Hydrogen Sulfide are from the California Office of Environmental Health Hazard Assessment.

N-Heptane

Heptane is used as a solvent.

Short term exposure to n-hexane can result in irritation to the eyes, skin, and mucous membranes.

Currently there are no standards set for evaluating risks of exposure to N-Heptane.

N-Hexane

N-Hexane is commonly found in petroleum products and is used to dilute paints.

Regulatory agencies set different standards for upper limits of a chemical's concentration in air considered to be "safe". It is possible that more than one standard could seem to apply in evaluating the potential health risk of a particular situation. Usually, the standard that is officially applied is the one set by the local regulating agency (or agencies).

The standards for regulation of exposure to N-Hexane are from the California Office of Environmental Health Hazard Assessment. No acute exposure standard is set by OEHHA.

N-Octane

N-Octane is a hydrocarbon that is used in gasoline.

N-Octane causes respiratory tract irritation.

Currently there are no standards set for evaluating risks of exposure to N-Octane.

PM2.5

Particulate matter (PM) is a complex mixture of tiny naturally occurring and man-made particles that consists of dry solid fragments, solid cores with liquid coatings, and small droplets of liquid. These particles vary greatly in shape, size and chemical composition, and can be made up of many different materials such as metals, soot, soil, pollen and dust. Fine particles are 2.5 microns or less in diameter (PM 2.5).

Particulate matter that is 2.5 microns or less cannot be expelled from the lungs, can penetrate lung tissue and enter the blood stream.

Exposure to fine particles can cause short-term health effects such as eye, nose, throat and lung irritation, coughing, sneezing, runny nose and shortness of breath. Exposure to fine particles can also affect lung function and affect medical conditions such as bronchitis, asthma, and heart disease.

California currently has an annual standard of 12 ug/m3 for PM 2.5 and uses the daily EPA standard of 35 ug/m3 per day.

Trimethylbenzene

Trimethylbenzene is an aromatic hydrocarbon with a strong odor. It occurs naturally in coal tar and petroleum.